This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH] Add tree rest of compilation timevar
Actually, I've got a more general question: do people find this timevar stuff
useful in understanding compilation performance? If so, what do they find it
useful for?
I find it only useful at the macro level. IE to see that PRE as a pass is
taking 40 seconds, or 40% of the compilation time, or whatever.
I then go profile PRE and see what's up.
I don't consider it's resolution good enough for small compilations, of
course.
Besides, turning on
-ftime-report changes the compilation time so much that I'm not sure I should
believe it anyway.
Darwin is the only platform i've ever seen this happen on (timevars take a
significant amount of time).
:)
I've always found it humorous that they show up on my profiles. I figure
one of these days, the kernel people or libc (or whatever is the cause of
the performance problem) will learn to do whatever everyone else is doing
to not need 2-10% of the compilation time just manipulating timers.
--Dan